FIRST QUESTION???
What happened to the original fork???
There are lots of reasons listed above as to why the fork is missing... One that hasn't been mentioned: a PO replaced the steel fork with a carbon fiber fork on classic racing bike...
Back when this was commonplace, lots of 1Di0Ts threw away the original steel fork because... why would anyone want to go back to something old fashioned. Also some just misplaced the original fork or lost it in moves and so on.
Getting back to original fork issues, I bought an early 80's Motobecane Team Champion frame on eBay back in 2007 and did a local pickup. As I walked up to the seller he held it out. From 20 feet away I could tell the fork was
WRONG!!! It was a Tange 27" replacement fork!
First thing I did was feel under the top and down tubes at the head tube - there were slight ripples! It was such a beautiful frame, I was sick!
After some discussion, I took it to a frame builder friend and we checked the alignment. It was OK even with the ripples but the 27" replacement fork caused the frame to sit 1/2" higher in the front which changed the front end geometry. I negotiated about a 50% refund with the seller and started assembling it but was so bummed out that it sat for about 8 years.
Years later I bought a 1980's Gitane that came with 2 forks. They had the same crown and geometry as the original Motobecane fork so I finished it with that Gitane fork.
I only rode it a few times and didn't like the handling so I sold it last year.
BTW, I've checked the alignment on all the frames and bikes that I've acquired. I can check and realign most of them at home. If it takes more, I have my frame builder friend do the work.
verktyg